In so far as a vehicular door mirror is concerned, a door mirror unit is assembled via a shaft to a door mirror base which is fixed to a vehicular side part (a door side).
The door mirror unit is made turnable at a folded storage position at which a mirror surface faces the door side about the shaft and a deployed use position at which the mirror surface faces a vehicular rear side while a phase is varied at a required angle from the folded storage position.
Thus, for example, as shown in Patent Literature 1, a rotation moderation mechanism is provided at a respective one of a shaft and a bearing portion of a door mirror unit so that the deployed use position of the door mirror unit can be appropriately retained.
In so far as the rotation moderation mechanism is concerned, a plurality of recessed and protrusion engagement portions to engage the shaft and the bearing portion from each other in a vertical direction are provided on a same planar circumference and to these recessed and protrusion engagement portions, a pressing force in the vertical direction is imparted by a spring so that the recessed and protrusion engagement portions engage with or disengage from each other in a rotation direction due to a rotation operation of the door mirror unit to thereby retain a required rotation position with a sense of moderation.